Door check



.June 21, 1958l s. w. PARSONS ET AL 2,839,777

DOOR CHECK Filed Jan. l14, 1955 MM. mh

Y uw N NN s www n TGA N wmp V M T mme .m wif mi U0 l a@ m. @N Q Lilli DOORI-CI-IECK Stuart W. Parsons, New Britain,.and-G.eorge E; Gilpatrick, West Hartford, Conn., assignorsto The Stanley Works, YNew Britain, Conn., a corporation of Connecticut Application January 14,.1955,`.SerialNo.. 481,892

8 Claims. (Cl.l16'66) The present invention relates.to'improvements.: in 4door checks of the type commonly usedon screen andvstorm doors, generally in combination withidoor-closer means.-

Door checks ofthe aforesaid -typegenerally include a cylinder -in which checking uid isA compressed by a piston during closing of the door andfrfromiwhich the fluid is allowed to escape through a restricted.Y outlet or `bleed passage at a rate suchk as. toretardk thedoorclosing movement to prevent slamming.l The associated door closer generally includes afspring which is loaded -by opening of the door and whiclnprovides the force necessary to close the door.

It has heretofore been a problem in the-operationof such door checks to obtain a satisfactory` adjustment of the rate of escape of the checking` fluid from the cylinder such that the door will ,close without undue delay when opened wide, yet will notslam when opened a small amount. The diilicultyV arisesfrom=the fact that when the bleed passage is adjustedto have a suiiciently. small ow rate to insure gentlevclosing ofthe door from a small angle of opening, door closing from a wideopen position is extremely slow and pressure-inthe checking cylinder may build up.r sufficiently to cause-objectionable bouncing of the piston onrthechecking tluid, with accompanying oscillations of the. door, which of course further delays the closing movement; and when the size of the bleed passage is increased sufficiently to permit the door to close trema wide-open position without bouncing of the piston: or excessive delay, the door will not be checked enough when openedthrough only a small angle and will therefore slam; As4 a'resultg. the adjustment of vprior art devices of` this type has -generally been limited to a compromise between these; ex,-V tremes whichisnot entirely'satisfactoryfon either.v

One object'of the present invention; therefore, is` to provide in a door check of the; characteridesmibedimeans for automatically controlling the' 'ratei ofy escape. of the checking flu-idduring doorclosing-sofas topreventrboth door slamming'and bouncing oftherpiston on thecheeking fluid; Y

Another object is to. provide i'n such-a.'doorrchcck improved ilowregulating means for *ther checking tluid bleed passage which compensates automaticaily'fordiferences in the amountofdoor opening or varying external forces applied to the door and enables the door to close quickly, yet gently, regardless vof the-angle: through wh'ich it is opened or the external forcer-applied Vtoit.,`

Another object` is-to provide in--a'- doorh check` an improved ilow regulating'valv'e -forfthechecking: fluid bleed passage which automatically and'continuou'sl'y ad'- justs the bleed passage flow rate-in accordance-with the pressure developed in the checking fluidi-during.y doorclos ing, and tends to equalize the door.v closingperiod-tor various angles of door opening. v

Another object isv to provide-inadoor checken improved checking fluid bleedvalvebf. simple-andinex.- pensive construction. which automatically regulates .flow

ing fluid, which is .small in' size, which requires nol ad` justment when once installed, and Which is capable of operating dependably for long. periods without care or attention of' any kind..

Other objects will be in part obvious, and-in part pointed out more in detaillhereinafter.

The inventionl accordingly. consists inthe features of construction7 combination'4 of. elements. and arrangement of parts which will. bey exemplified. in the construction hereafter sety forth and the; scope ofi the application of which will be-indicated in the appended claims.

In the drawing:

.Figure l is a'vertical sectional View of a combination door check and door-closer having a bleed passage ow contro1 valve constructed in accordance with/the present invention; and

Figure 2 is a vfragmentary sectional view of a portion of the door check of Figure 1, illustrating the manner of operation of the flow control valve during closing of the door.

Referring to the drawing, the invention is illustrated in connection-with a combination door check and door closer including a checking cylinder 2 adapted to contain-checking fluid, which in the instant embodiment is air, a piston 4 inthe cylinder'mounted on a piston rod 6;. and a door-closingrspring. The spring 8 illustrated is of the torsion type andis shown enclosed within the door check, but it should-be understood that the spring may be of-anydesired'type and may be mounted in any desired-manner,- the invention being-in no sense limited tothe type of door closer or mounting arrangement rate in accordance with pressure developed in the check- Y Y employed.

The check- .is adapted to be secured to a door frame headerv by a mounting plate 10.A Depending from the plate 10'- 'is an elongate screw- Ztl-supporting a cover i3 on which is rotatably mounted a concentric barrel-shaped knuckle-or housing 16.y The housing is open at its top and-:has a horizontally extending boss 32 formed with a cylindrical recess 36in which one end of the checking; cylinder 2 is secured; Thepiston-rod 6 extends through a cap 315- at the other end ofthe cylinder and is pivotally connected by pin 14' toa bracket 12 which is adapted to befastened to -a door.

Surrounding the screw 20 is a sleeve 22 of square cross section-which is secured at its lower end to the cover -S- and has -xedat its upper end a ratchet wheel 24. engageablewith a paw1f26-on-the mounting plate. The spring; 8 isenclosed within the housing 16, being hooked thereto at its upper-end and secured at its lower end to al disc 28 which is slidably, but non-rotatably, mounted on the square sleeve 22. With this arrangement the spring may be adjusted to vprovide any desired amount of initial door-closing. bias by merely rotating the cover 1S,y sleeve 22 and ratchetwheel'24 relative to the-housing, so as to wind up the spring-the necessary amount. The bottom of the cover isdiametrically groovedas at 29- to permit insertion of a bar or the like, facilitating rotation of the ycover tofwind up-the spring- The piston-4 includes a'cupeshaped-:exible packing 36 clamped 4between a washer 3S .and a backing-plate 49,',and mounted' on theV piston-trod xby nuts 42. The outletr bleed` passage throughi whichz-theair compressed in the cylinderby the piston is allowed to escape includes a bore Silliurthe wall ofthe housing; 16: at the bottom of recess 30. With this arrangement openingofthe door moves the piston to theV right and'adrnits to-the left of thepiston a charge ofV airproportional.. to the, piston displacement. The door opening movement, also swings the cylinder and-rotates housing 16 about its axis, thereby increasing the. loading zon. spring 28 so as to. provide the necessary yforce to close the door. When the door is released,V the spring. S rotates the housing back `to its Patented June 24, 19t-"a8V initial position and, as the door closes, the movement of the piston in a left-hand direction compresses the air in the cylinder and checks the door closing movement in accordance with the rate of'escape ofV air through outlet bore 50.

In accordance with the invention, the rate of escape of checking fluid from the cylinder is controlled by a flow regulating valve which is automatically and continuously adjusts the ilow of air through the outlet bleed passage in accordance with the pressure developed in the checking cylinder. The valve consists of a wafer or disc S2 of elastic material which is dished on one side to form a central portion 53 whose thickness progressively decreases towards its center. At the center of portion 53 the valve has an extremely small hole 54, which of necessity has been greatly magnified in the drawing, but which in reality is scarcely visible to the naked eye, being of the order of only a few thousandths of an inch in diameter. The material for the valve may be any suitable elastomer such as, for example, neoprene.

The valve is disposed within the end of the cylinder formed by recess 30 so as to cover bore 50, and its peripheral portion is firmly clamped against the radial shoulder 55 of the recess by a washer 56 which may be integral with the cylinder 2. The dished side of the valve faces the piston 4 and behind the central portion 53 of the valve the wall of the housing is relieved to provide a shallow pocket 58 forming a concave surface surrounding the inner end of bore S0.

In the operation of the door check with the valve 52, as the piston 4 movesto the right during door opening some air flows into the cylinder through opening 54 and augments the How of air past packing 36 in forming the air charge on the left side of the piston. During the door closing movement air is compressed in the cylinder and is expelled through the central opening 54 in the valve and through outlet bore 50. Since the opening 54 is quite small, for small angles of door opening the valve will effectively throttle the escape of air from the cylinder and insure gentle closing of the door without slamming. As the door is opened wider, however, increasing the return force of the spring 8 and correspondingly increasing the air pressure in the cylinder 2, the thin central portion 53 of the valve is automatically ballooned out or distended into the pocket S by the increased air pressure, as shown in Figure 2, and the opening 54 is thereby expanded and automatically increases the rate of air escape from the cylinder, The valve thus automatically provides an increased air discharge rate when it is needed to dispel the larger air charge formed behind the piston when the door is opened wide, and thereby prevents excessive pressure build-up which might cause bouncing of the piston on the air charge or otherwise excessively delay the door closing. Hence the valve tends to equalize the door closing period for all angles of door opening. Since the valve is sensitive to checking fluid pressure, it also compensates automatically for the application of external forces such as wind force on the door, increasing the air escape rate as necessary to prevent piston bouncing and provide smooth door closing without slamming under all circumstances. and the pressure in the cylinder tends toV fall, the elastic valve will automatically distend to a lesser degree and the size of the hole 54 will be reduced accordingly, so that the door will not speed up and slam, but will continue to close gently until it latches.

The mounting arrangement and shape of the valve as above described provide many advantages which contribute to improved door operation and long valve life. The rm clamping of the peripheral portion of the valve between shoulder S5 and washer 56 prevents air leakage around the valve as well as preventing the peripheral portion of the valve from being pulled radially As the door closing movement continuesy out of position when the central portion is distended. The progressively decreasing thickness of the dished central portion 53 of the valve provides a cantilever action when the valve distends which enables the thickness of the valve at opening 54 to be a minimum, and 'thus permits opening 54 to vary in size with maximum sensitivity to air pressure in the cylinder while avoidingstretching of the valve out of shape during operation. The bottom surface of the pocket 58 provides a stop limiting outward bulging of central portion 53, and thereby preventing rupture of the valve or stretching beyond its elastic limit as well as limiting the maximum size of opening 54 so that wind or other external forces on the door cannot cause it to slam.

Thus it may be seen that the valve compensates automatically for differences in the air pressure developed in the cylinder, thereby regulating operation of the door check automatically in response to different amounts of door openings or various external forces on the door so as to prevent both slamming of the door and undue delay in closing of -the door. When once installed, the valve requires no further -adjustments of any kind, but will operate automatically to regulate the pressure in the cylinder as required to provide smooth fand substantially uniform door closing regardless of the angle at which the door is opened. The valve is simple and inexpensive in construction, as well as small in size and, since the particular shape and mounting 'arrangement of the valve protects it 'against acquiring a permanent set, the valve will operate dependably for long periods without care or attention of any kind.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween,

We claim: s

l. In a door check having a cylinder and a piston mounted for reciprocation in the cylinder responsive to door movement 'and adapted to pressurize checking fluid in the cylinder to retard `closing of the door, means forming an escape for iluid pressurized in the cylinder comprising a valve including an elastic wafer having a distensible portion with a minute aperture therein providing the sole passage through said valve through which checking fluid pressurized in the cylinder may escape and mounting means for the wafer forming an open pocket on the side of the wafer opposite from the piston and dimensioned to permit the wafer to distend and vary thc size of the said valve aperture responsive to iluid pressure thereon, whereby variations in the closing force on the door are automatically compensated for by distension of said distensible portion and resultant expansion of said aperture in accordance with the pressure of said checking fluid.

2. In a door check having a cylinder and a piston mounted for reciprocation in the cylinder responsive to `door movement and `adapted to pressurize checking uid in the cylinder to retard closing of the door, escape means for iluid pressurized in the cylinder comprising a valve including an elastic wafer having a central distensible portion, said central portion having a thickness progres'- sively diminishing toward its center and having a minute aperture at its center.

" 3.. In a door check having a cylinder and a piston mountedtfor reciprocation in the cylinder responsive to door movement and adapted to pressurize checking iluid rin the cylinder to retard closing of the door, means forming an outlet passage to permit the escape of fluid pressurized in the cylinder, means for regulating flow of fluid through said outlet passage comprising an elastic wafer having a central outwardly distensible portion covering the outlet passage and provided with a minute aperture at its center providing the sole passage for checking fluid from said cylinder to said outlet passage, and a surface surrounding the outlet passage and outwardly spaced from said distensible portion to provide a stop limiting outward movement of said distensible portion.

4. In ya door check having a cylinder, a piston mounted for reciprocation in the cylinder responsive to door movement :and adapted to pressurize checking fluid in the cylinder to retard closing of the door, means forming an outlet passage to permit the escape of fluid pressurized in the cylinder, means for regulating flow of fluid through said outlet passage comprising an elastic wafer having a central outwardly distensible portion closing the outlet passage, said central portion having a thickness progressively diminishing toward its center and having a minute aperture at its center, and a surface surrounding the outlet passage and outwardly spaced from said distensible portion to provide a stop limiting outward movement of said distensible portion.V

5. In a door check having a cylinder, means providing7 an air outlet of fixed cross sectional area for the cylinder, a piston mounted for movement in the cylinder in one direction during Vdoor opening movement and in the other direction during door closing movement and arranged to compress air in the cylinder to check closing of the door, means for regulating ow of air through the outlet comprising a valve including an elastic disc having a centrally disposed distensible portion covering the outlet and having a minute central aperture providing the sole air low passage through said valve, and means anchoring the peripheral portion of said disc in fixed relation with said outlet.

6. In a door check having a cylinder, a piston mounted for reciprocation in the cylinder responsive to door movement and arranged to compress air in the cylinder to check closing of the door, means providing an outlet passage of fixed diameter for said cylinder for releasing air compressed therein, means for regulating flow of air through the outlet passage comprising a valve including a disc of elastic material having a peripheral portion secured to the cylinder and having a central outwardly distensible portion closing the outlet passage, said central portion having a thickness progressively diminishing toward its center and having a minute aperture at its center, and a surface surrounding the outlet passage in outwardlyspaced relation to said distensible portion and with which said distensible portion may engage t when distended to limit elastic material.

7. In a door check having a cylinder containing checking fluid, a reciprocable piston in the cylinder attachable to a door for movement in one direction responsive to opening of the door and in the other direction responsive to closing of the door, and means forming a wall closing one end of the cylinder between which and said piston fluid is pressurized in the cylinder during door closing movement, said wall having an outlet of fixed cross sectional area for releasing fluid pressurized in the cylinder, means for regulating flow of fluid through the outlet in accordance with fluid pressure in the cylinder comprising a plate of elastic material having a distensible thin portion surrounded by a peripheral portion, a holder securing said peripheral portion to said wall to prevent fluid ow past said peripheral portion with said distensible thin portion covering said outlet and exposed on its inner side to the pressure in said cylinder, said distensible sponsive to door movement and arranged to compress checking fluid therein during closing of the door to retard door closing movement, means providing an enclosing wall for the cylinder having an outlet passage of fixed diameter through which fluid pressurized in the cylinder v may escape, said regulating means comprising an enlarged portion at the inner end of said outlet passage forming an inwardly facing pocket in said wall surrounded by a radial shoulder, a disc of elastic material having a peripheral portion clamped against said shoulder and vhaving a central portion covering said pocket and outwardly distensible thereinto responsive'to pressure in said cylinder, said central portion being dished on its inner side and having a minute` perforation at its center variable in size responsive to distension of said central portion of the disc.

References Cited in the le of'this patent UNITED VSTATES PATENTS 1,848,574 More Mar. 8, 1932 2,478,717 Simpson Aug. 9, 1949 2,543,565 Billngsley Feb. 27, 1951 FOREIGN PATENTS 2,333 Great Britain Feb. 2, 1894 

